The intestinal epithelium separates luminal contents from the interstitium. This function is primarily determined by the integrity of the epithelium and the tight junction that seals the paracellular space. These intestinal tight junctions are selectively permeable. This permeability can be increased physiologically in response to the presence of luminal nutrients. Permeability can also be increased pathologically by mucosal immune cells and cytokines, the enteric nervous system, and by pathogens. It is believed to be critical that the intestinal mucosa prevent potentially dangerous contents of the intestinal lumen, including the microorganisms that reside there from entering internal areas and the systemic circulation. There are several clinical conditions, both intestinal and systemic, that are associated with compromised intestinal barrier function.
A possible link between intestinal hyperpermeability and disease has been proposed. This has led to a sharp increase in the diagnosis of intestinal hyperpermeability, also known as “leaky gut syndrome.” Diseases that have been correlated with intestinal hyperpermeability include diabetes, autism, fibromyalgia, inflammatory bowel disease (IBD), graft versus host disease (GVHD), HIV/AIDS, multiple organ dysfunction syndrome, irritable bowel syndrome (IBS), celiac disease, eczema, psoriasis, acute pancreatitis, Parkinson's disease, depression, chronic fatigue syndrome, asthma, multiple sclerosis, arthritis, ankylosing spondylitis, nonalcoholic fatty liver disease, alcoholic cirrhosis, environmental enteropathy, and kwashiorkor. It is believed that restoration of the intestinal barrier will improve or cure the underlying disease. Several drug targets that could potentially promote barrier restoration have been proposed, but none have proven safe and effective.
Thus, there remains a need for the development of safe and effective treatments or cures for intestinal hypersensitivity and numerous underlying diseases.